타일 금형 라이너 및 끼움재의 열박음 공차 및 결합력에 대한 해석적 연구

임동욱,이정식,정영호,최두선,고강호,이정우,김재훈,Lim, Dong Wook,Lee, Jeong Sik,Jeong, Young Ho,Choi, Doo Sun,Ko, Kang-Ho,Lee, Jeong-woo,Kim, Ji-Hun 한국금형공학회 2020 한국금형공학회지 Vol.14 No.3

Ceramic tile is widely used as a floor or interior decoration of buildings. The main processes are raw material blending, molding, drying, firing, etc., and since dimensional and quality stability are very important, they are generally molded by a dry press method. In ceramic tile molds, there is a liner that can be easily replaced in case of wear. The liner is constantly abrasion due to a continuous pressing process during tile forming, and it is required to be replaced every certain period. Even in the liner, use a wear-resistant fitting material only in areas where wear is concentrated. However, there was a risk that the fitting material was applied to large-sized tile molding due to problems such as damage to the molding machine and decrease in productivity when detached during the actual tile molding process due to weak fitting strength with the liner. Therefore, in this study, thermal-structural analysis for fitting tolerance analysis and structural analysis for fitting force analysis were performed for the shrink fit process of the fitting material.

유한요소법을 이용한 유압브레이커 Cylinder와 Piston의 열-구조 연성해석을 통한 안정성 평가

임동욱,박윤수,신봉철,Lim, Dong-Wook,Park, Yoon-Soo,Shin, Bong-Cheol 한국금형공학회 2018 한국금형공학회지 Vol.12 No.1

This study proves the causes of cylinder and piston jam by scratches which is the fatal problem of hydraulic breaker through the thermal analysis and thermal-structural coupled field analysis. The trouble from the scratch is a complex problem which can be caused by manufacturing process (this is an internal factor) and the users mistake or contamination in the hydraulic circuit (these are an external factor). Hence, it's not easy to investigate the causes, also hard to prevent the recurrence. In this reason, hydraulic breaker manufacturers are trying to improve the manufacturing process such as machining, heat treatment, grinding, cleaning, also to prevent the contamination in hydraulic circuit and to remove the remains. It's being managed thoroughly by manufacturers. This study shows the effect of the temperature rise by the frictional heat generated when the piston hits the tool on the hydraulic oil while the hydraulic breaker is operating, also the temperature distribution when it starts to affect main components of hydraulic breaker. The stress and the amount of deformation also could be found through thermal-structural coupled field analysis. It proved that the stress and deformation are proportionally increased according to the temperature rise in hit area, and it affects the cylinder and the viscosity of hydraulic oil inside the cylinder when it heats up beyond the certain temperature.

금형 냉각 최적화를 위한 기체 보조 냉각

임동욱,김지훈,신봉철,Lim, Dong-Wook,Kim, Ji-Hun,Shin, Bong-Cheol 한국금형공학회 2018 한국금형공학회지 Vol.12 No.1

Both injection and injection molding dies have evolved into advanced technology. Product quality is also evolving day after day. Therefore, the conditions of the injection mold and the injection conditions are becoming important. In order to improve the quality of the product, the Hardware part of the mold has developed as an advanced technology, and the Software part has also developed with advanced technology. This study deals with the cooling part, which is part of the hardware. In addition to fluid cooling, which is commonly used in the industry, by using gas cooling identify the phenomena that appear on the surface of the product and the critical point strain of the product to find the optimal cooling. Electronic parts and automobile parts whose surface condition is important, the cooling process is important to such a degree that they are divided with good products and defective products according to the cooling process at the time of injection. By controlling this important cooling and reducing the injection time with additional cooling, the product quality can be increased to the highest production efficiency. In addition, high efficiency can be achieved without additional investment costs. This study was conducted to apply these various advantages in the field.

유한요소해석을 이용한 마이크로 분사 노즐 특성 평가

임동욱,최두선,김태민,박정래,박규백,함휘찬,김지훈,Lim, Dong-Wook,Choi, Doo-Sun,Kim, Tae-min,Park, Jung-Rae,Park, Kyu-Bag,Ham, Hwi-Chan,Kim, Ji-Hun 한국금형공학회 2020 한국금형공학회지 Vol.14 No.3

In the drug delivery system industry, the technology with even split injection becomes important for maximizing efficiency and minimizing the side effects. In conventional drug delivery system, infection can occur due to pain and splashing. Also, various applications are impossible due to disposable use, and it is the reason to avoid to use this system because of the complexity of the driving method. Therefore, in this study, a painless drug delivery device is developed for non-pain with electrical insulation breakdown method. Finite elements analysis was used to evaluate the ejection characteristics of drugs according to the shape of the micro ejection nozzle. The effect of the number of holes in the micro nozzle, the length of the nozzle and the inner shape of the nozzle on the drug discharge characteristics were analyzed.

MR fluid를 이용한 알루미늄 표면의 초정밀 연마 방법

임동욱,김병찬,홍광표,조명우,Lim, Dong-Wook,Kim, Byung-Chan,Hong, Kwang-Pyo,Cho, Myung-Woo 한국금형공학회 2017 한국금형공학회지 Vol.11 No.2

Recent industrial developments are constantly advancing, and rapid technological development is demanding high technology level in related fields. The need for polishing is increasing even more to improve quality. In order to improve the surface quality, the final finishing process or polishing process is a very important part. Research on super precise polishing method using MR fluid is actively being carried out in domestic and foreign countries. Fine magnetic abrasive grains are aligned in the direction of a magnetic force line formed by a magnetic field and serve as a brush to polish a metal surface. This method has the advantage that the shape of the tool is not fixed and is not affected by the shape of the workpiece or the machining area. We will design the electromagnets for the MR polish polishing system and apply the magnetic field analysis using the magnetic field analysis program (ANSYS). The data obtained through this process suggests an efficient method to increase the magnetic flux density important for polishing. We will investigate the influence of the Al6061-T6 specimen on the surface of the MR polishing machine based on the optimized design.

Calcium and CN bimodality of RGB stars in Globular clusters with Multiple Populations

임동욱,노동구,한상일,이영욱,Lim, Dongwook,Roh, Dong-Goo,Han, Sang-Il,Lee, Young-Wook 한국천문학회 2012 天文學會報 Vol.37 No.2

A number of recent observations have established that many globular clusters have double or multiple stellar populations. In particular, recent Calcium and Stromgren b & photometry shows a split in the RGB of some of these globular clusters, including M22, NGC 1851, and NGC 288. However, the origin of this split in the RGB is still controversial. In order to confirm the real difference in Calcium abundance between the two RGBs, we have performed low resolution spectroscopy for RGB stars in these globular clusters. The spectral data were obtained from WFCCD/duPont 2.5m telescope in Las Campanas Observatory. We found a significant bimodality of both Calcium and CN abundances in M22 and NGC 1851. NGC 288, however, shows a clear bimodality only in CN abundance.

삼킴장애 분석을 위한 멀티프레임 의료영상 라벨링 웹 애플리케이션 구현

임동욱 ( Dong-wook Lim ),이충섭 ( Chung-sub Lee ),노시형 ( Si-hyeong Noh ),박철 ( Chul Park ),김민수 ( Min Su Kim ),문희경 ( Hee-kyung Moon ),정창원 ( Chang-won Jeong ) 한국정보처리학회 2023 한국정보처리학회 학술대회논문집 Vol.30 No.1

삼킴장애는 음식물이 입에서 식도로 가지않고 걸리거나 기도(Trachea)로 흡입되는 문제를 갖는 상태이다. 특히 노인이나 신경계 질환을 앓는 환자의 경우 기도로 흡입된 음식덩이가 폐렴을 일으키고 결국에는 사망으로 이어지기에 적절한 치료와 관리가 요구된다. 보통 영상으로 판단할 수 있는 삼킴단계는 구강준비단계(Oral Preparatory Phase), 구강단계(Oral Phase), 인두단계(Pharyngeal Phase), 식도단계(Esophageal Phase) 4가지로 분류하고 삼킴장애는 침습(Penetration)과 흡인(Aspiration)으로 크게 2가지로 분류한다. 본 논문에서는 이러한 6가지 클래스를 가지는 삼킴장애 환자 비디오 파일을 라벨링하기 위한 웹 애플리케이션을 제안한다. 이를 구현하기 위해서 대용량 멀티프레임 이미지를 수신해서 분리하여 저장하도록 개발하였다. 또한 음식덩이를 정교하게 분할할 수 있도록 GrabCut 알고리즘을 적용하여 라벨링할 수 있도록 하였다. 차후 라벨러와 전문의 간의 협업이 가능하도록 라벨링 데이터의 상태를 관리할 수 있도록 개발하고자 한다.

전기 자극으로 유발한 음경 발기력 측정 흰쥐 모델에 대한 HTE001의 발기력 상승효과

임동욱 ( Dong Wook Lim ),이동헌 ( Dong Hun Lee ),송미경 ( Mi Kyoung Song ),김미연 ( Mi Yeon Kim ),부영민 ( Young Min Bu ),김호철 ( Ho Cheol Kim ) 대한본초학회 2009 大韓本草學會誌 Vol.24 No.3

Objectives: This study was conducted to investigate the effect of HTE001, a multi-herbal mixture consisting of 10 herbs, Cornus Frutus, Schizandrae Fructus, Rubi Fructus, Cnidi Fructus, Acanthopanacis senticosi Radix, Cinnamomi Cortex, Eucommiae Cortex, Allii Bulbus, Rehmanniae Radix and Ginseng Radix, on electrostimulation-induced penile erection in rats. Methods: Intracavernous pressure (ICP) and mean arterial blood pressure (MAP) were simultaneously monitored through electric stimulation of the cavernous nerve after the oral administration of HTE001 (30, 100, 300 mg/kg) in normal rats. Statistical analysis was performed on maximal intracavernous pressure (ICP), maximal intracavernous pressure/mean arterial blood pressure (ICP/MAP) ratio, and the area under the curve (AUC) of ICP/MAP ratio. Results: Oral administration of HTE001 300 mg/kg caused the ICP to increase in a frequency-dependent manner. And HTE001 300 mg/kg treatment group showed the highest value in the ICP/MAP ratio and the AUC value of the ICP/MAP ratio compared to the control group at 2 Hz, 6 Hz and 10 Hz, respectively without an effect on the mean arterial blood pressure under the same stimulation of the cavernous nerve. Conclusions: These results show that HTE001 improve penile erection and prolong the decay period in normal rats without affecting mean arterial blood pressure, and suggest that HTE001 could be a good therapeutic candidate to treat erectile dysfunction.

가미귀비탕이 (加味歸碑湯) 면역조절작용에 미치는 영향

임동욱(Dong Wook Lim),유동열(Dong Youl You) 대한한방부인과학회 1999 大韓韓方婦人科學會誌 Vol.12 No.2

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검사 신호에 대한 저비용 압축

임동욱(Dong Wook Lim),민형복(Hyoung Bok Min) 한국정보과학회 1998 정보과학회논문지 : 시스템 및 이론 Vol.25 No.11

조합 회로에 대한 검사 신호 자동 생성 알고리즘들이 단일 고착 결함에 대해서는 적은 비용으로 완전한 고장 검출률을 성취해감에 따라, 작은 크기의 검사 신호 집합을 계산하는 문제가 중요시되고 있다. 검사 신호 집합의 크기를 압축하면 다음과 같은 장점이 있다. (1) 검사 신호를 실제 회로에 적용하는데 드는 시간이 줄어든다. (2) 검사 신호를 저장하는데 필요한 저장 장치의 요구량이 감소된다. 본 논문에서는 새로운 검사 신호 압축 알고리즘을 사용하는 검사 신호 자동 생성 알고리즘을 제안한다. 이 검사 신호 압축 알고리즘은 적은 계산 시간을 보장하며 작은 크기의 검사 신호를 생성한다. 이 알고리즘은 COMPACTEST의 세 가지 경험적 알고리즘인 최대 독립 결함 집합, 회전형 역방향 추적, 그리고 복수개의 대상 결함을 고려한 검사 신호 자동 생성 알고리즘들을 변형하여 사용한다. 제안한 알고리즘의 효율을 입증하기 위해 본 논문은 기반 검사 신호 자동 생성 알고리즘으로서 PODEM을 사용하였고, 실험 대상 회로로서 ISCAS85 회로를 사용하였다. 실험 결과에 의하면, 본 논문은 기존 검사 신호 자동 생성 알고리즘의 고장 검출률을 저하시키지 않으면서 PODEM 알고리즘과 비교하여, 약 36%의 검사 신호 압축률을 보였고, 계산 시간에 있어서는 오히려 약 28%의 감소를 보였다. Test generation procedures for combinational circuits are practically capable of achieving complete coverage of single stuck-at faults in a cost-effective manner. In such situation, the problem of deriving small(compact) test sets gains importance. The advantages of a small test set are the followings. (1) Test application time is shorter. (2) Storage requirements of tests in testing hardware are reduced. In this paper, we present an automatic test pattern generation procedure with a new compaction algorithm, which aims at producing a small test set with reduced CPU time. In the algorithm, we use three modified heuristics of COMPACTEST such as maximal independent fault set, rotating backtrace, and multiple target fault test generation. We have used PODEM as an underlying test generator system and experimented on the ISCAS85 benchmark circuits to show the cost-efficiency of the proposed algorithm. Experimental results compared with PODEM show about 36% compaction of test set and 28% decrease of test generation time without affecting fault coverage.